Injection regimen for anesthesia of the maxillary first molar

Edema and hematoma after local anesthesia via posterior superior alveolar nerve block: a case report

Although rare, complications can occur with anesthetic procedures. The posterior superior alveolar nerve (PSAN) block anesthetic technique has a high success rate, but positive aspiration can cause bruising, transient diplopia, blurred vision, and temporary blindness in approximately 3% cases. When edema occurs, it is occasionally massive, especially in the infratemporal fossa, and the resulting hematoma is usually unsightly. A 20-year-old woman presented with massive edema followed by hematoma in the upper right jaw immediately after PSAN block administration, which subsequently spread to the oral mucosa. The patient did not report any complications during the anesthetic procedure. However, after the injection was administered, the patient experienced anesthetic sensations, which rapidly evolved to facial edema. There was mild pain, but without intraoral or extraoral bleeding. The patient was prescribed medicines and instructed to perform contrast therapy. Although hematomas and edema are rare, they are difficult to prevent. The choice of local anesthetic and appropriate application of the anesthetic technique can minimize their occurrence.

Efficacy of intraligamentary anesthesia in maxillary first molar extraction

INTRODUCTION

Infiltration anesthesia (IA) is the method to anaesthetize maxillary teeth successfully. In contrast, intraligamentary anesthesia (ILA) has been used as supplementary anesthesia during tooth extraction, particularly when regional block anesthesia has failed. In this study, we compare the efficacy of and patient satisfaction with ILA vs IA when extracting maxillary first molar teeth.

METHODS

Forty patients were enrolled in this study and 80 maxillary first molars extracted. All patients served as their own control, with ILA as the experimental side and IA as the control side. The two techniques were compared for efficacy using a visual analog scale (VAS) and patient satisfaction compared using a verbal rating scale (VRS).

RESULTS

The mean VAS pain score for extraction using ILA was lower than that for IA (20.30±3.18 and 13.93±1.95 mm, respectively; P<0.001). For injection pain, the mean VAS pain score in the ILA side was higher than the IA side (42.28±4.51 and 31.73±3.1 mm, respectively; P<0.001). VRS results showed a higher number of patients who felt that pain during ILA was greater than expected compared with IA.

CONCLUSION

IA appears less painful during injection compared with ILA, and provides sufficient pain relief during extraction. However, ILA can be used when IA fails to achieve the desired pain suppression, as it provides higher extraction-pain relief.

Anaesthesia Techniques for Maxillary Molars - A Questionnaire-Based Retrospective Field Survey of Dentist in Western India

INTRODUCTION

Clinicians use various anaesthesia techniques like Posterior Superior Alveolar (PSA) nerve block, buccal infiltration with or without supplemental anaesthesia like palatal and intraligamentary infiltrations for root canal treatment in maxillary molars. However there is no general consensus regarding which technique is enough for performing endodontic treatment in maxillary molars.

AIM

The aim of this questionnaire-based survey is to compare and evaluate the various techniques used to anaesthetize the maxillary molars and its effect on postoperative pain.

MATERIALS AND METHODS

The data were obtained from 290 dental practitioners using a specially prepared questionnaire survey conducted anonymously. The questionnaire contained questions covering data such as years in dentistry, acquired specialty, techniques used for anaesthetizing maxillary molars, success of anaesthesia, and postoperative pain, etc.

RESULTS

Buccal infilteration with supplemental anaesthesia in the form of palatal (82%) and intra-ligamentary infilteration (88%) show higher success rate compared to only buccal infilteration (69%). However, intra-ligamentary infilteration group showed highest rate (75%) of postoperative pain. General practitioners (62% of clinicians) prefer to give both buccal and palatal infilterations and specialists opt for only buccal infilteration (66-74% of specialists).

CONCLUSION

Only buccal infilteration is sufficient during root canal treatment of maxillary molars. Routine use of supplemental anaesthesia in the form of palatal and intra-ligamentary infilteration is not necessary unless patient experiences discomfort during endodontic treatment. However, intra-ligamentary infilteration may lead to postoperative discomfort in the form of pain.

Effect of Three Different Injection Sites on the Success of Anterior Middle Superior Alveolar Nerve Block with 3% Mepivacaine: A Randomized Controlled Trial

AIM

Anterior middle superior alveolar (AMSA) nerve block injection targets the anterior superior alveolar nerve and the middle superior alveolar nerve branches of the infraorbital nerve through nutrient canals. Therefore, the central incisor to the second premolar teeth of one quadrant can be anesthetized. The aim of the present study was to evaluate the efficacy of AMSA nerve block injection with 3% mepivacaine solution at three different injection sites.

MATERIALS AND METHODS

In a double-blind crossover study, 47 volunteers participated and three AMSA nerve block injections of 3% mepivacaine solution without epinephrine were administered at the anterior, posterior, and the most common injection sites with a 1-week interval between injections. Anesthesia of the central incisor to the second premolar of the injected side was evaluated by using an electric pulp tester. The success of the injection was considered as lack of response to two consecutive 80 readings. The generalized estimating equation analytic tests were administered (α = 0.05).

RESULTS

The success rate of the AMSA nerve block injection ranged from 27.5-47.5% for the most common injection site and 22.5-42.5% for both the anterior and posterior injection sites.

CONCLUSION

Changing the injection site did not result in statistically significant improvements (p > 0.05).

CLINICAL SIGNIFICANCE

Changing the injection site anteropos-teriorly did not influence the success rate of the AMSA nerve block injection.

Posterior superior alveolar nerve blocks: a randomised controlled, double blind trial

BACKGROUND

Local anesthesia has been a boon for dentistry to allay the most common fear of pain among dental patients. Several techniques to achieve anesthesia for posterior maxillae have been advocated albeit with minor differences. We compared two techniques of posterior superior alveolar nerve block (PSANB), the one claimed to be "most accurate" to the one "most commonly used."

AIM

This study was conducted to assess and compare the efficacy as well as complications of "the straight needle technique" to that of "the bent needle technique" for PSANB.

PATIENTS AND METHODS

We conducted a prospective, randomised, double blind study on 120 patients divided into two groups, using a 26-gauge, 38 mm long needle with 2 ml of 2 % lignocaine hydrochloride with 1:200,000 adrenaline solution. Objective symptoms were evaluated by a single investigator. Cold test using ice was used to evaluate the status of pulpal anesthesia. Data thus obtained was subjected to statistical analysis.

RESULTS

Out of the 120 blocks, 19 blocks failed. Statistical analysis found straight needle technique to be more successful than the bent needle technique (p = 0.002). Both the techniques were equally effective for the first molar region on both right and left side (p = 0.66 on right side and p = 0.20 on left side). However, in the second and third molar region technique A was more effective than B (p = 0.01) on right side only. On Left side, both techniques were equally effective (p = 0.08). Sensitivity of the cold test was 82 % which is quite high but the specificity was 68 % which seems to be falling in the above average range only. Positive predictive value of 75 and negative predictive value of 76 was observed. We did not encounter any complications in this study.

CONCLUSION

To the best of our knowledge, this is the first randomised controlled clinical study on PSANB techniques. This study suggests that the PSANB using the straight needle technique as advocated by Malamed [1] can be routinely and safely used to achieve anesthesia in the maxillary molar region and to great efficacy, with normal precautions.

Efficacy of single buccal infiltrations for maxillary first molars in patients with irreversible pulpitis: a randomized controlled clinical trial

AIM

To evaluate the efficacy of a single buccal infitration using 4% articaine hydrochloride (HCl) with 1 : 100,000 epinephrine or 4% articaine HCl with 1 : 100 000 epinephrine bitartrate for obtaining adequate pulpal anaesthesia in the palatal roots of maxillary first molars associated with irreversible pulpitis.

METHODOLOGY

In this single-blind randomized clinical trial, fifty subjects were randomly allocated to receive maxillary buccal injections of 1.5 mL 4% articaine with 1 : 100,000 epinephrine (n = 25) or 1.5 mL 4% articaine with 1 : 100,000 epinephrine bitartrate (n = 25). Visual analogue scale (VAS) scores and pulse rate measurements were recorded during access cavity preparation and initial file placement into the mesiobuccal, distobuccal and palatal canals. Data were analysed using Duncan and t-tests.

RESULTS

There was no significant difference between the two anaesthetic solutions regarding the VAS scores and pulse rate measurements during endodontic procedures. The mean VAS ratings of the 50 patients during file placement into the palatal canals were significantly higher compared with the other three root canal procedures (P < 0.0001). The heart rates during negotiation of palatal canals were significantly higher than when negotiating the mesiobuccal and distobuccal canals (P < 0.0001).

CONCLUSION

Single buccal infiltration did not achieve adequate pulpal anaesthesia in the palatal root canal of the maxillary first molars associated with irreversible pulpitis.

Efficacy and feasibility of frontozygomatic angle approach for extra oral maxillary nerve block in oral surgery: a descriptive clinical trial

BACKGROUND

Pain control is an integral part of minor oral surgery and maxillary/mandibular nerve blocks have proved promising in achieving the same. Although intra oral techniques of maxillary nerve block are common and are widely used, there are certain inherent disadvantages and potential complications. Less commonly described in the literature, the extra oral techniques have a wide spectrum of indications as well as can be more advantageous than the intra oral approach. This prospective clinical trial is an attempt to evaluate the feasibility and the efficacy of the extra oral frontozygomatic approach to the foramen rotundum to block the maxillary nerve.

MATERIALS AND METHODS

Sample size was 100 patients and the inclusion criteria were patients of ASA I or II category who needed extraction of a minimum of 4 maxillary teeth in the same quadrant in a single sitting while exclusion criteria were patients with a history of allergy to local anesthesia, medically compromised patients in whom dental extraction was contraindicated. Mean age was 71.9 years and 56 patients were males while 44 were females. Only a single quadrant (first or second) was chosen as the operative site in each patient and local anaesthesia was secured using a 21 gauge 89 mm long spinal needle with frontozygomatic angle approach and the parameters used were pain experienced during the injection, onset of subjective symptoms, time required for the peak effect (objective symptoms), pain during extraction and the duration of anesthesia. All the parameters were expressed as mean values with standard deviations.

RESULTS

A successful anesthesia was secured in first attempt in 98 patients while in 2 patients, the procedure had to be repeated owing to the difficulty in reaching the target site. A majority of the patients i.e., 71 % scored 0-2 (no pain) on visual analogue scale (VAS) while only 2 patients experienced a moderate degree of pain. Subjective symptoms were reported in 27.24 s (mean value) and 12.93 s (mean value) in the palate and the infraorbital fossa respectively. Peak effect of anesthesia was noted in 66.7, 37.38 and 31.71 s (all values expressed as mean) in palate, infraorbital fossa and posterior superior alveolar areas respectively.

CONCLUSION

Although with only dental extraction as the procedure of choice, the present study has favoured the frontozygomatic angle approach for the maxillary nerve block as simple, safe, efficacious and associated with minimum and clinically mild complications.

A prospective, randomized, single-blind comparative evaluation of anesthetic efficacy of posterior superior alveolar nerve blocks, buccal infiltrations, and buccal plus palatal infiltrations in patients with irreversible pulpitis

INTRODUCTION

The purpose of this study was to evaluate and compare the anesthetic efficacy of posterior superior alveolar (PSA) nerve blocks, buccal infiltrations, and buccal plus palatal infiltrations with 2% lidocaine with 1:200,000 epinephrine in maxillary first molars with irreversible pulpitis.

METHODS

Ninety-four adult patients participated in this prospective, randomized, single-blinded study. The patients were divided into 3 treatment groups on a random basis. Twenty-eight patients received a PSA nerve block, 33 patients received buccal infiltrations, and 33 patients received buccal plus palatal infiltrations with 2% lidocaine with 1:200,000 epinephrine. Endodontic access preparation was initiated 15 minutes after injection. Pain during treatment was recorded using a Heft-Parker visual analog scale. Success was recorded as "none" or "mild" pain.

RESULTS

Statistical analysis using nonparametric chi-square tests revealed that there was no statistical difference between the anesthetic success of PSA nerve blocks (64%), buccal infiltrations (54%), and buccal plus palatal infiltrations (70%).

CONCLUSIONS

None of the tested methods gave 100% anesthetic success rates in maxillary first molars with irreversible pulpitis.

A review of the mandibular and maxillary nerve supplies and their clinical relevance

Mandibular and maxillary nerve supplies are described in most anatomy textbooks. Nevertheless, several anatomical variations can be found and some of them are clinically relevant. Several studies have described the anatomical variations of the branching pattern of the trigeminal nerve in great detail. The aim of this review is to collect data from the literature and gives a detailed description of the innervation of the mandible and maxilla. We carried out a search of studies published in PubMed up to 2011, including clinical, anatomical and radiological studies. This paper gives an overview of the main anatomical variations of the maxillary and mandibular nerve supplies, describing the anatomical variations that should be considered by the clinicians to understand pathological situations better and to avoid complications associated with anaesthesia and surgical procedures.

Anatomy of greater palatine foramen and canal and pterygopalatine fossa in Thais: considerations for maxillary nerve block

This study aims to investigate the anatomy of the greater palatine foramen (GPF), greater palatine canal (GPC) and pterygopalatine fossa (PPF) with special reference to the blockage of the maxillary nerve. A correlation between the length of GPC and PPF and the heights of the orbit and the maxilla was also studied using simple linear regression analysis. The morphology of the GPF, GPC and PPF as well as heights of the orbit and the maxilla were assessed in 105 Thai skulls. The thickness of the mucosa over the GPF was also measured from the dissection of 55 cadavers. The results showed that most GPF appeared as an oval foramen located at the palatal aspect of the upper third molar. The GPF was 16.2+/-1.3 mm lateral to the median sagittal plane of the hard palate, 2.1+/-1.3 mm anterior to the posterior border of the hard palate and 5.1+/-1.3 mm from the greatest concavity of the distolateral margin of the hard palate. The mean length of GPC and PPF was 29.7+/-4.2 mm. The mean angles of the GPC in relation to the hard palate and the vertical plane were 57.9+/-5.8 degrees and 6.7+/-5.2 degrees , respectively. In attempting to insert a needle to reach the foramen rotundum through the GPF, 31.7% passed into the orbit while 8.7% passed into the brain. The mean thickness of the mucosa over GPF was 6.7+/-2.3 mm. Two models for estimating the depth of needle injection in maxillary nerve block have been developed as follows: Length of GPC and PPF=19.038+0.314 (orbital height) and length of GPC and PPF=21.204+0.187 (maxillary height). The calculated length combined with the mucosal thickness was the estimated depth of needle injection. In conclusion, our results concerning the GPF, GPC and PPF will provide the useful reference for clinicians to anesthetize the maxillary nerve with a greater degree of success.

Clinical significance of the length of the pterygopalatine fissure in dental anesthesia

OBJECTIVE

This study determined the average length of the pterygopalatine fissure by using human cadavers. Recommendations are made to improve the success of maxillary nerve block injections.

MATERIALS AND METHODS

Pterygopalatine fissures were dissected, exposing the maxillary nerve trunk in 47 human cadavers. The length of the fissure was measured from the maxillary nerve to the buccal sulcus. The angle between the fissure and the occlusal plane was also recorded.

RESULTS

The average fissure length was 36.7 mm, making an approximately 60 degrees angle to the occlusal plane. Fissures from females were statistically significantly shorter than those from males. There was no difference with respect to ethnic group. Cadaver length was the best predictor of fissure length.

CONCLUSIONS

Depth of penetration with a needle that is longer than that normally available is necessary to predictably ensure a successful maxillary nerve block.

Patterns of innervation of the maxillary first molar: a dissection study

Human maxillae were dissected with the aim of tracing nerves from maxillary first molar root apices to their parent superior alveolar nerve branches. The contribution of the posterior, middle, and anterior superior alveolar nerves to the innervation of the first molar was assessed. The posterior superior alveolar nerve was found to contribute innervation 100% of the time; the middle superior alveolar nerve, when present, contributed innervation 28% of the time. The anterior superior alveolar nerve did not supply any innervation to the first molar.